Explanation:

- The passage suggests that science has both positive and negative impacts on life. It mentions that science makes life better and easier but also acknowledges the creation of destructive tools.

- Science has improved medical practices, with discoveries helping alleviate pain and cure diseases.

- The goal of these scientific advancements is to allow humans to live longer and healthier lives.

- Option 1: tedious – This implies a boring or monotonous life, which does not align with the context of the passage.

- Option 2: healthier – This fits perfectly, as the passage discusses improvements in health due to scientific advancements.

- Option 3: productive – While a longer, productive life is positive, it does not focus on health.

- Option 4: bigger – This is not relevant to the theme of health and longevity.